Handle "p S::method()::static_var" in the C++ parser

This commit makes "print S::method()::static_var" actually find the
debug symbol for static_var.  Currently, you get:

  (gdb) print S::method()::static_var
  A syntax error in expression, near `'.

Quoting the whole string would seemingly work before the previous
patch that made GDB stop assuming int for no-debug-info variables:

  (gdb) p 'S::method()::static_var'
  $1 = 1

... except that's incorrect output, because:

  (gdb) ptype 'S::method()::static_var'
  type = <data variable, no debug info>

The way to make it work correctly currently is by quoting the
function/method part, like this:

  (gdb) print 'S::method()'::static_var
  $1 = {i1 = 1, i2 = 2, i3 = 3}
  (gdb) ptype 'S::method()'::static_var
  type = struct aggregate {
      int i1;
      int i2;
      int i3;
  }

At least after the "stop assuming int" patch, this is what we
now get:

  (gdb) p 'S::method()::static_var'
  'S::method()::static_var' has unknown type; cast it to its declared type
  (gdb) p (struct aggregate) 'S::method()::static_var'
  $1 = {i1 = 1, i2 = 2, i3 = 3}

However, IMO, users shouldn't really have to care about any of this.
GDB should Just Work, without quoting, IMO.

So here's a patch that implements support for that in the C++ parser.
With this patch, you now get:

  (gdb) p S::method()::S_M_s_var_aggregate
  $1 = {i1 = 1, i2 = 2, i3 = 3}
  (gdb) ptype S::method()::S_M_s_var_aggregate
  type = struct aggregate {
      int i1;
      int i2;
      int i3;
  }

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	(%type <voidval>): Add function_method.
	* c-exp.y (exp): New production for calls with no arguments.
	(function_method, function_method_void_or_typelist): New
	productions.
	(exp): New production for "method()::static_var".
	* eval.c (evaluate_subexp_standard): Handle OP_FUNC_STATIC_VAR.
	* expprint.c (print_subexp_standard, dump_subexp_body_standard):
	Handle OP_FUNC_STATIC_VAR.
	* parse.c (operator_length_standard):
	Handle OP_FUNC_STATIC_VAR.
	* std-operator.def (OP_FUNC_STATIC_VAR): New.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/local-static.c: New.
	* gdb.base/local-static.cc: New.
	* gdb.base/local-static.exp:  New.

1 files changed, 142 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.cp/local-static.c b/gdb/testsuite/gdb.cp/local-static.c
new file mode 100644
index 0000000..5bfff8d
--- /dev/null
+++ b/gdb/testsuite/gdb.cp/local-static.c
@@ -0,0 +1,142 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2002-2017 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+struct aggregate
+{
+  int i1;
+  int i2;
+  int i3;
+};
+
+void keepalive_float (double *var) { }
+void keepalive_int (int *var) { }
+void keepalive_aggregate (struct aggregate *var) { }
+
+#define PREFIXIFY(PREFIX, VAR)			\
+  PREFIX ## _ ## VAR
+
+#define DEF_STATICS(PREFIX)						\
+  static int PREFIXIFY(PREFIX, s_var_int) = 4;				\
+  static double PREFIXIFY(PREFIX, s_var_float) = 3.14f;			\
+  static struct aggregate PREFIXIFY(PREFIX, s_var_aggregate)		\
+    = { 1, 2, 3 };							\
+									\
+  keepalive_int (&PREFIXIFY(PREFIX, s_var_int));			\
+  keepalive_float (&PREFIXIFY(PREFIX, s_var_float));			\
+  keepalive_aggregate (&PREFIXIFY(PREFIX, s_var_aggregate));
+
+#ifdef __cplusplus
+
+struct S
+{
+  void inline_method ()
+  {
+    DEF_STATICS (S_IM);
+  }
+  static void static_inline_method ()
+  {
+    DEF_STATICS (S_SIM);
+  }
+
+  void method ();
+  static void static_method ();
+};
+
+S s;
+
+void
+S::method ()
+{
+  DEF_STATICS (S_M);
+}
+
+void
+S::static_method ()
+{
+  DEF_STATICS (S_SM);
+}
+
+template <typename T>
+struct S2
+{
+  void method ();
+  static void static_method ();
+
+  void inline_method ()
+  {
+    DEF_STATICS (S2_IM);
+  }
+
+  static void static_inline_method ()
+  {
+    DEF_STATICS (S2_SIM);
+  }
+};
+
+template<typename T>
+void
+S2<T>::method ()
+{
+  DEF_STATICS (S2_M);
+}
+
+template<typename T>
+void
+S2<T>::static_method ()
+{
+  DEF_STATICS (S2_SM);
+}
+
+S2<int> s2;
+
+#endif
+
+void
+free_func (void)
+{
+  DEF_STATICS (FF);
+}
+
+static inline void
+free_inline_func (void)
+{
+  DEF_STATICS (FIF);
+}
+
+int
+main ()
+{
+  for (int i = 0; i < 1000; i++)
+    {
+      free_func ();
+      free_inline_func ();
+
+#ifdef __cplusplus
+      s.method ();
+      s.inline_method ();
+      S::static_method ();
+      S::static_inline_method ();
+
+      s2.method ();
+      s2.inline_method ();
+      S2<int>::static_method ();
+      S2<int>::static_inline_method ();
+#endif
+    }
+
+  return 0;
+}